[PATCH] (2.4.25 material?) Fix unbalanced helper_lock in kernel/kmod.c

[Nigel Cunningham <nigel@nigel.suspend2.net>]

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Hi all.

First up, sorry for not inlining the patch - trouble with line wrapping.

In 2.6.24-rc8, call_usermodehelper_exec has an exit path that can leave
the helper_lock() call at the top of the routine unbalanced. The
attached patch fixes this issue.

Signed-off-by: Nigel Cunningham <nigel@tuxonice.net>




[-- Attachment #2: helper-lock-fix.patch --]
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diff --git a/kernel/kmod.c b/kernel/kmod.c
index c6a4f8a..de27e15 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -468,8 +468,10 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info,
 	sub_info->wait = wait;
 
 	queue_work(khelper_wq, &sub_info->work);
-	if (wait == UMH_NO_WAIT) /* task has freed sub_info */
+	if (wait == UMH_NO_WAIT) { /* task has freed sub_info */
+		helper_unlock();
 		return 0;
+	}
 	wait_for_completion(&done);
 	retval = sub_info->retval;